Blog
Einstein's gravitational waves detected in landmark discovery

WASHINGTON/CAMBRIDGE, Mass. Scientists for the first time have detected gravitational waves, ripples in space and time hypothesised by Albert Einstein a century ago, in a landmark discovery announced on Thursday that opens a new window for studying the cosmos.The researchers said they identified gravitational waves coming from two distant black holes - extraordinarily dense objects whose existence also was foreseen by Einstein - that orbited one another, spiraled inward and smashed together at high speed to form a single, larger black hole.The waves were unleashed by the collision of the black holes, one of them 29 times the mass of the sun and the other 36 times the solar mass, located 1.3 billion light years from Earth, the researchers said."Ladies and gentlemen, we have detected gravitational waves. We did it," said California Institute of Technology physicist David Reitze, triggering applause at a packed news conference in Washington."It's been a very long road, but this is just the beginning," Louisiana State University physicist Gabriela Gonzalez told the news conference, hailing the discovery as opening a new era in astronomy.The scientific milestone was achieved using a pair of giant laser detectors in the United States, located in Louisiana and Washington state, capping a decades-long quest to find these waves."The colliding black holes that produced these gravitational waves created a violent storm in the fabric of space and time, a storm in which time speeded up, and slowed down, and speeded up again, a storm in which the shape of space was bent in this way and that way," Caltech physicist Kip Thorne said.The scientists first detected the waves last Sept. 14.The two instruments, working in unison, are called the Laser Interferometer Gravitational-Wave Observatory (LIGO). They detected remarkably small vibrations from the gravitational waves as they passed through the Earth. The scientists converted the wave signal into audio waves and listened to the sounds of the black holes merging. At the news conference, they played an audio recording of this: a low rumbling pierced by chirps."We're actually hearing them go thump in the night," Massachusetts Institute of Technology physicist Matthew Evans said. "There's a very visceral connection to this observation." 'A NEW SENSE'"We are really witnessing the opening of a new tool for doing astronomy," MIT astrophysicist Nergis Mavalvala said in an interview. "We have turned on a new sense. We have been able to see and now we will be able to hear as well." While opening a door to new ways to observe the universe, scientists said gravitational waves should help them gain knowledge about enigmatic objects like black holes and neutron stars. The waves also may provide insight into the mysterious nature of the very early universe.The scientists said that because gravitational waves are so radically different from electromagnetic waves they expect them to reveal big surprises about the universe.Everything we knew until now about the cosmos stemmed from electromagnetic waves such as radio waves, visible light, infrared light, X-rays and gamma rays. Because such waves encounter interference as they travel across the universe, they can tell only part of the story.Gravitational waves experience no such barriers, meaning they offer a wealth of additional information. Black holes, for example, do not emit light, radio waves and the like, but can be studied via gravitational waves. Einstein in 1916 proposed the existence of gravitational waves as an outgrowth of his ground-breaking general theory of relativity, which depicted gravity as a distortion of space and time triggered by the presence of matter. Until now scientists had found only indirect evidence of their existence, beginning in the 1970s.Scientists sounded positively giddy over the discovery."This is the holy grail of science," said Rochester Institute of Technology astrophysicist Carlos Lousto."The last time anything like this happened was in 1888 when Heinrich Hertz detected the radio waves that had been predicted by James Clerk Maxwell’s field-equations of electromagnetism in 1865," added Durham University physicist Tom McLeish.Abhay Ashtekar, director of Penn State University's Institute for Gravitation and the Cosmos, said heavy celestial objects bend space and time but because of the relative weakness of the gravitational force the effect is miniscule except from massive and dense bodies like black holes and neutron stars.A black hole is a region of space so packed with matter that not even photons of light can escape the force of gravity. Neutron stars are small, about the size of a city, but are extremely heavy, the compact remains of a larger star that died in a supernova explosion.The National Science Foundation, an independent agency of the U.S. government, provided about $1.1 billion in funding for the research over 40 years. (Reporting by Will Dunham in Washington, Irene Klotz in Cape Canaveral, Florida, and Scott Malone in Cambridge, Mass.; Editing by Tom Brown)

Read More
Einstein's gravitational waves detected in scientific milestone

WASHINGTON/CAMBRIDGE, Mass. Scientists have for the first time detected gravitational waves, ripples in space and time hypothesized by Albert Einstein a century ago, in a landmark discovery announced on Thursday that opens a new window for studying the cosmos.The researchers said they detected gravitational waves coming from two distant black holes - extraordinarily dense objects whose existence also was foreseen by Einstein - that orbited one another, spiraled inward and smashed together. They said the waves were the product of a collision between two black holes roughly 30 times the mass of the Sun, located 1.3 billion light years from Earth."Ladies and gentlemen, we have detected gravitational waves. We did it," said California Institute of Technology physicist David Reitze, triggering applause at a packed news conference in Washington."It's been a very long road, but this is just the beginning," Louisiana State University physicist Gabriela Gonzalez told the news conference, touting the opening of a new era in astronomy.The scientific milestone was achieved using a pair of giant laser detectors in the United States, located in Louisiana and Washington state, capping a decades-long quest to find these waves."The colliding black holes that produced these gravitational waves created a violent storm in the fabric of space and time, a storm in which time speeded up, and slowed down, and speeded up again, a storm in which the shape of space was bent in this way and that way," Caltech physicist Kip Thorne said.The two laser instruments, which work in unison, are known as the Laser Interferometer Gravitational-Wave Observatory (LIGO). They were able to detect remarkably small vibrations from passing gravitational waves. After detecting the gravitational wave signal, the scientists said they converted it into audio waves and were able to listen to the sounds of the two black holes merging. "We're actually hearing them go thump in the night," Massachusetts Institute of Technology physicist Matthew Evans said. "We're getting a signal which arrives at Earth, and we can put it on a speaker, and we can hear these black holes go, 'Whoop.' There's a very visceral connection to this observation." The scientists said they first detected the gravitational waves last Sept. 14. "We are really witnessing the opening of a new tool for doing astronomy,” MIT astrophysicist Nergis Mavalvala said in an interview. “We have turned on a new sense. We have been able to see and now we will be able to hear as well.”Einstein in 1916 proposed the existence of gravitational waves as an outgrowth of his ground-breaking general theory of relativity, which depicted gravity as a distortion of space and time triggered by the presence of matter. But until now scientists had found only indirect evidence of their existence.OPEN THE DOOR Scientists said gravitational waves open a door for a new way to observe the universe and gain knowledge about enigmatic objects like black holes and neutron stars. By studying gravitational waves they also hope to gain insight into the nature of the very early universe, which has remained mysterious.Everything we know about the cosmos stems from electromagnetic waves such as radio waves, visible light, infrared light, X-rays and gamma rays. But because such waves encounter interference as they travel across the universe, they can tell only part of the story.Gravitational waves experience no such barriers, meaning they can offer a wealth of additional information. Black holes, for example, do not emit light, radio waves and the like, but can be studied via gravitational waves.The scientists said that because gravitational waves are so radically different from electromagnetic waves they expect them to reveal big surprises about the universe.Scientists sounded positively giddy over the discovery. "This is the holy grail of science," said Rochester Institute of Technology astrophysicist Carlos Lousto. "The last time anything like this happened was in 1888 when Heinrich Hertz detected the radio waves that had been predicted by James Clerk Maxwell’s field-equations of electromagnetism in 1865," added Durham University physicist Tom McLeish."It is really a truly, truly exciting event," said Abhay Ashtekar, director of Penn State University's Institute for Gravitation and the Cosmos. "It opens a brand new window on the universe."Ashtekar said heavy celestial objects bend space and time but because of the relative weakness of the gravitational force the effect is miniscule except from massive and dense bodies like black holes and neutron stars. He said that when these objects collide, they send out ripples in the curvature of space and time that propagate as gravitational waves.A black hole, a region of space so packed with matter that not even photons of light can escape the force of gravity, was detected for the first time in 1971.Neutron stars are small, about the size of a city, but are extremely heavy, the compact remains of a larger star that died in a supernova explosion.The LIGO observatories are funded by the National Science Foundation, an independent agency of the U.S. government. (Reporting by Will Dunham in Washington, Irene Klotz in Cape Canaveral, Florida, and Scott Malone in Cambridge, Mass.; Editing by Tom Brown)

Read More
Twitter's new timeline: Waiting is the hardest part

There wasn't a big switch. Twitter's new timeline didn't just appear after it was announced on Wednesday the site would officially get a "Show Me Best Tweets First" design based on relevancy, rather than chronology. Worse yet, the news arrived without a single image showing how to turn on (or off) the feature in settings, or how the new Tweet order would look to users. This was odd. See also: Twitter's new timeline is here, and it's all about the algorithm In the brief blog post about one of Twitter's most significant service changes in years — a post that was, strangely, not written by Twitter CEO Jack Dorsey — the company doesn't even properly describe its own settings. "Just go into the timeline section of your settings and choose 'Show me the best Tweets first,'" the blog post by Mike Jahr reads. However, there's no "Timeline" section in settings. There is, on the desktop version, a "Notifications timeline" setting, but that's not the the same thing, is it? Fortunately, there are more explicit instructions available, but you have to find them by following a link from Jahr's post and scrolling down to a set of steps that, as I was writing this, did not match the current state of Twitter. Even though Jahr's post used the word "now," the update was actually rolling out slowly, and the iOS and Android features may have required an app reinstall (or maybe even an app update). All morning, I scoured Twitter and couldn't find anyone who was enjoying or hating the new feeds. The hours of waiting for this new timeline algorithm gave me ample time to think about how it works. Twitter's details on this point are scant: "We choose them based on accounts you interact with most, Tweets you engage with, and much more." The first part is pretty clear. When I retweet or favorite (heart) an account a lot, its tweets will likely get priority in this Timeline "Best Tweets" block. Interaction could also include Direct Messaging, I guess, though that feels a bit invasive. However, I don't understand how Twitter can measure tweets I engage with if I haven't seen them. In other words, if Twitter's algorithm chooses which new/best Tweets to front load, shouldn't they be tweets I haven't read and engaged with? Then there's the "much more" portion, which is the KFC Secret Recipe of the new Twitter Timeline Algorithm. We may never know all the ways in which Twitter's algorithm is managing our new feed. The fact that this algorithm now exists, though, means that whatever it does right now, it could be doing something different in the future. We need only to look a few clicks over to Facebook's ever-changing Newsfeed algorithm to know this. I know Twitter needs this — or something like this — to make the service more inviting to newbies, but what if it doesn't work? At some point Twitter is going to have to accept something that most long-time users already know: Unlike Facebook, Twitter simply isn't for everyone — and that's OK. Now excuse me while I go back to waiting. Have something to add to this story? Share it in the comments.

Read More
Yelp posts smaller-than-expected loss; CFO to step down

Consumer review website operator Yelp Inc reported a smaller-than-estimated loss on Monday, but its shares slumped 12 percent, swept up in a broader selloff in the technology sector.The company said its results were released ahead of schedule due to a vendor error by PR Newswire, leading to a spike in volatility in its shares.Yelp also said Chief Financial Officer Rob Krolik would step down. Krolik, who joined the company in 2011, will continue in his current role till Dec. 15, 2016, or until a replacement is hired, the company said in a statement.Yelp's revenue rose about 40 percent in the fourth quarter, topping analysts' estimates, helped by the strength in its advertising business and a rise in mobile usage.Local advertising accounts in the quarter rose 32 percent to about 111,000, which was in line with estimates from market research firm FactSet StreetAccount. The San Francisco-based company has been trying to expand outside the United States and diversify into services such as restaurant bookings, event management and payments to counter increasing competition.Yelp competes with OpenTable in the restaurants booking business and Angie's List Inc in the listings business. In December, Facebook Inc quietly debuted a feature that helps users find local businesses based on customer reviews that could emerge as a strong competitor.The company said it expected to report net revenue of $154 million-$157 million in the first quarter, largely above the $154.4 million estimated by the analysts. Yelp reported a net loss of $22.2 million, or 29 cents per share, attributable to common stockholders for the quarter ended Dec. 31, compared with a profit of $32.7 million, or 42 cents per share, a year earlier. On an adjusted basis, the company posted a loss of 2 cents per share, while analysts were expecting a loss of 3 cents, according to Thomson Reuters I/B/E/S. Revenue rose to $153.7 million from $109.9 million. Analysts had expected revenue of $152.4 million for the quarter.Yelp's shares were down 11.5 percent at $16.02 in afternoon trading on Monday. They fell as much as 15 percent in early session, touching a more than three year low of $15.50.(This version of the story corrects day of week to Monday instead of Wednesday, last paragraph) (Reporting by Alan John Koshy and Lehar Maan in Bengaluru; Editing by Anil D'Silva)

Read More
India says yes to net neutrality, no to Facebook's Free Basics

In a significant move, India's telecom regulator has banned the differential pricing for different kinds of data according to the principles of net neutrality. This implies that zero-rating initiatives like Facebook's Free Basics platform, which offers a small set of services free of cost, will not be allowed in the country. See also: India’s telecom regulator accuses Facebook of running an 'orchestrated opinion poll' for Free Basics “Given that a majority of the population are yet to be connected to the Internet, allowing service providers to define the nature of access would be equivalent of letting TSPs (telecom service providers) shape the users’ Internet experience,” the Telecom Regulatory Authority of India (TRAI) said in its release. Its new set of regulations bars any service provider from offering or charging discriminatory tariffs on the basis of content and and imposes a fine of Rs 50,000 ($735) per day on violators. "While formulating the regulations, the authority has largely been guided by the principles of net neutrality seeking to ensure that customers get unhindered and non-discriminatory access to the Internet," TRAI said in its statement. However, it has exempted reduced tariff plans in times of emergency. The order concluded TRAI's consultation paper issued on Dec. 9, 2015, which invited stakeholders to send their views on the differential pricing of different content, until Jan. 14, 2016. This period saw a massive advertising campaign by Facebook to promote Free Basics, which was countered by a volunteer-led coalition called Save the Internet, that was supported by major Indian startups. Last month, TRAI also criticised Facebook's lobbying campaign as a "crudely majoritarian and orchestrated opinion poll." Great to see TRAI backing #NetNeutrality! Let's keep the Internet free and independent. — Kunal Bahl (@1kunalbahl) February 8, 2016 This was Facebooks Waterloo in India. It lost respect in tech community, showed its ignorance and arrogance https://t.co/JFGOr2WblS — Vivek Wadhwa (@wadhwa) February 8, 2016 Well TRAI'ed Mark Zuckerberg. Hard Luck #NetNeutrality — Joy (@Joydas) February 8, 2016 Have something to add to this story? Share it in the comments. window._msla=window.loadScriptAsync||function(src,id){if(document.getElementById(id))return;var js=document.createElement('script');js.id=id;js.src=src;document.getElementsByTagName('script')[0].parentNode.insertBefore(js,fjs);}; _msla("//platform.twitter.com/widgets.js","twitter_jssdk");

Read More
Older Post